Combined multiband electrical structure and switching mechanism



25 Q6 7 /zez 23% :72 Iffl/ff 2f April 27, 1937. G, HARRISON I 2,078,908

COMBINED MULTIBAND ELECTRICAL STRUCTURE AND SWI'ICHINGr MECHANISM4 Filed March 28, 1954 :s sheets-sheet 1 [u F 52 J 25,., n ma, [WC 53 f/d ,l-lxvyf Imaam 3% 441 44424 42 4442 Z4/,6% /e 'Z INVENTOR A G. HARRlsoN COMBINED MULTIBAND ELECTRICALSTRUCTURE AND SWITCHING MECHANISM 3 Sheets-Sheet. 2

Filled March 28, 1954 fill! rifa.

ATTORNEY April 27,211937. l G .HARmSON 1 2,078,908

COMBINED MULTBAND ELECTRICAL STRUCTURE AND SWITCHING MECHANISM Filed March 28, 1934 3 Sheets-Sheet` 3 znon 550m lNVENTOR Patented Apr. 27, 1937 t -UNITED STATES MnlNEn v MULTmANp ELECTRICAL sTa'UCTUaE AND swrTCumG MECH- e ANIsM Gale Harrison, Kearny, N. J., assignor to Radio Corporation of America, New York, N. Y., a corporation of Delaware Application March 28, 1934, Serial No. 717,868

25 Claims.

This invention relates to a combination multispeech frequencies, carrier frequencies, radio frequencies and quasi-optical frequencies.

Another object of my invention is to provide a unitary structure as set forth in the principal object, which is so designed that the mechanism may be quickly set on any one of the frequency bands within the range of the instrument.

A further object of my invention is to provide a complete unitary structure made up of a plurality of quickly separable coupling units, and

each of these units made up of supplemental or circuit units arranged in cooperative position within the coupling umts, whereby the proper circuit umts may be brought into operation for the particular frequency band with which it is to be associated. y

A further object of my invention is to provide a. single unitary structure composed of a plurality of couplingunits, the parts of which are so constructed and arranged that they may be vreadily assembled or dis-assembled.

A still further object of my invention isto provide a structure of the class described which is relatively simple and easy and cheap to manufacture when the nature of the apparatus istaken into consideration.

Theseand other objects will be understood by one skilled in this art, from a reading of the specification taken in connection with the annexed drawings, wherein:

'Figure 1 is a side elevation of one form of my combination multi-band electrical structure and switching mechanism, as adapted to use for tunlng radio receivers.

Figure 2 is a section on the line 2-2 of Figure 1.

Figure 3 is a section on the line 3-#3 ofFigure 1.

Figure 4 is a section o n thek line I--I of Fig- 50 ure 1.

l Figure 5 is a horizontal sectional view on the axial center of Figure 1.

Figure 6 is a vertical central section through the front or control end of the device. g

55 Figure 7 is a view on the line 1-1 of Figure 6,

but with the drive plate turned thirty degrees from the showing in Figure 6.

Figure 8 is a view on the line 0-8 of Figure 6.

Figure 9 is a view on the line 9-9 of Figure 6, both Figures 8 and 9 showing the manner of 5 fastening the drive shaft to the forward drive plate.

Figure 10 is a part-sectional view on the line Iii-I0 of Figure 5.

Figure 11 is an exploded sectional view on the 10 line iI--Ii of Figure 10.

Figure 12 is a plan view ofthe switch Contact side of one of the circuit units.A

Figure 13 is a fragmentary perspective view. looking at one end of Figure 12. 15

Figure 14 is a section on 'the line Il-II of Figure 12.

Figure 15 is a bottom plan view of one of the frame switch units.

Figure 16 is a perspective view of one of the 20 switch contacts shown in Figure 15. ,Y

Figure 17 is an enlarged view of the switchengaging parts on the line i1--I1 of Figure 4.

Figure 18 is a verticalsectional view through the stop or positioning member shown `on the 2 extreme right hand side of Figure 5.

Figure 19 shows a modified form ofcircuit unit that may be used in one or moreof the coupling units.

Figure 20 is a view similar to Figure 19. but 30 of a still further modied form of circuit imit.

Figure 21 is a schematic diagram showing how my combination multi-band coil structure and switching mechanism may be utilized in a radio receiving system. 35

In the various views of the drawings, wherein like numbers refer to corresponding parts, l is a framey more or less skeleton in shape. having uprights or pedestals 2 and 3 at opposite ends thereof. Mounted on the pedestals 2 and 8, for 40 rotary movement, is a switching mechanism composed of a plurality of readily separable units which I prefer to refer to as coupling units, since these units contain other units which I shall hereinafter refer to as circuit units which carry parts that make up circuits for circuits of theA various coupling umts, whereby the circuit units may beA connected into a. complete radio receiving system. Preferably, for the purpose of ease and cheapness in manufacture, I prefer tomake as many parts of the coupling units, as well as the circuit units, in a similar manner. Forexample, referring particularly to Figures 1 and 5, each coupling unit includes a casing 4 preferably of metal ,so as to act as a shield for all of the parts enclosed by it.

As illustrated, the casing 4 is provided with similar caps 5 at each end. The cap 5 has a plurality of indentations 6 which may be of any desired shape. a circular shape being preferred as indicated.

Positioned between the cap 5 on one unit and the cap 5 on the next adjacent unit, is a circular insulating disc 'I having perforations therein to fit around circular-shaped insulators 8, which fits into the indentations 5 on the two adjacent caps 5. Thus it will be seen that the small insulating discs 8 act as driving or coupling means between the units. They also assist the insulator I in insulating one coupling unit from the other. While I have shown and described a band 4 having two caps 5 at either end, it is to be understood that a cup-shaped member 4 may be used in which the bottom part takes the place of one of the caps 5, it being understood that the depressions 6 are made in the bottom to correspond and cooperate with the similar depressions in the cap next adjacent the bottom of said cupshaped casing 4. Since this is an obvious modiiication, it has not been shown in the drawings.

At the right hand end of the structure, a driving plate 9, in the form of a circular disc, is used, the same being perforated to receive the insulators 8 as shown in Figures 6 and 7. Fastened to the driving disc 9 is a stub or drive shaft I0, the union between the two being made by depressing the metal at II as shown in Figure 9, and providing a collar I2 securely fastened to the shaft III, which collar fits in the depressed portion II. The end of the shaft to the left of the collar I2 passes through a hole in the plate 9 and has an upset head I3 as indicated' in Figure 8. The opposite end of the coil structure is provided with a similar plate 9 and a stub shaft I4, connected thereto in the same manner as has been described with respect to the drive shaft III. Likewise, a driving connection is made to the rear plate 9 in a similar manner as for the forward plate, all as clearly shown in Figure 5.

The pedestals 2 and 3 have clearance notches to receive the stub shafts I and I4, which, however, have bearings in similar bearing plates I5. Referring to the drive end bearing plate I5, this is provided with an indentation I on its inner face, which indentation is adapted to pass over a boss I1 extruded or punched, or formed, inwardly from the pedestal 2. The indentation I5 is provided with a tapped hole Il to receive a screw I8 for holding the plate I5 in position. In addition, the metal ofthe plate I5 is provided with an extended boss 2l preferably made by extruding the metal of the plate so as to provide a longer bearing surface for the shaft.

In assembling the structure, the two plates I5, similarly made as above described, are placed in position on their respective shafts and then the structure, with the plates, is slid downwardly inside of the pedestals 2 and I so that the indentations I8 pass over the guiding means or bosses I1, and then the screws I5 are put into place, thereby rotatably mounting, through the medium of the shaft III, stub shaft I4 and control knob 2I, the entire structure in the frame.

The casing 4 of each coupling unit is provided with a plurality of perforations or openings 22 through which project switch contacts or blades generally referred to as 22. The switch contacts'or blades 23 comprise parts of a circuit unit composed of a frame or support member having a body portion 24 and a stem 25 which may or may not be made integral with the body portion 24. As shown in several of the views. for

example Figure 2, the body or base portion 24 is shaped to fit the inner periphery of the wall of the casing 4, being held thereto in any satisfactory manner as by screws 25 as shown in Figure 1, which screws are adapted to enter screw-threaded holes 21 in the base portion 24.

The switch contacts or blades 22 may be attached to the base portion 24 in amr satisfactory manner. As shown in Figure 13, the blade has two tines 28 and 29 which pass through openings in the part 24, or-they may be moulded therein. Preferably the tine 25 of each switch blade is formed so as to extend beyond the contour of the portion 24 for the purpose of acting as terminals for the electrical devices carried on the stem 25. These electrical devices may be differently constructed and have different electrical characteristics.

As shown in Figure 2, the stem 25 carries two coils, a primary 30 and a secondary 3|, the terminals of the primary coil 20 being connected to contacts or switch blades a and b, while the ends of the secondary coil 2| are connected w vthe contacts or switch blades c and d, through their respective terminals 29. In Figure 3, the stem 25 carries a. pair of coils 32 and '23 disposed in different relationship from the coils shown in Figure 2. The coil 32 is connected to corresponding contacts a and b, and the coil Il to the contacts c and d, comprising a part of its circuit unit, similar to that described with respect to the coils shown in Figure 2. In Figure 4, the stem 25 carries a primary winding I4 and a secondary winding 25 wound together in one coil, and also a small condenser 25 which is connected as shown in the upper right-hand part of the diagram of Figure 21. The windings 24 and 25 are each connected to the switch blades 2l of its particular circuit unit.

Since these circuit units carry windings of different turns and sizes of wire, and are differently arranged, as well as condensers, I have referred to them in the claims as impedances. 4In other words, the circuitv units may carry resistances wound inductively or non-inductively, or windings in the shape of inductance coils, or condensers, so that all may be broadly included by the term impedances. Generally speaking, all the circuit units within the coupling unit A may follow the general order and arrangement of those shown in Figure 2, although this is not obligatory. The same may be said with respect to the design of the circuit units in the coupling units B and C, although certain of these circuit units may take the forms shown in'Figures 19 and 20, wherein primary and secondary coils are shown mounted on the stern 25, depending on the requirements of the wave band with which the circuit units are associated.

However, it is to be kept in mind that the impedances arranged on each circuit unit are such as to cooperate in the coupling units A, B and C to operate in a system covering the same wave band or range of frequencies. For example, in the diagram shown in Figure 2l, the switching mechanism, composed of the plurality of coupling units, is set to tune the input circuits of a hypothetical superheterodyne radio receiver to cover a certain band, for example the broadcast band from 200 to 550 meters; whereas, the sets of coils to the right, going in an anti-clockwise direction around the dotted circles shown in Figure 2l, are illustrative of an arrangement of impedances to cover the wave band from 750 to 2000 meters. 'rae next set or impedance: n roh wave band be varied according to the receiving system used.

As shown dlagrammatically in. Figure 2l, the coupling -A carries circuit units for the antenna circuits connected to the tube 31. The coupling B carries circuit units for the transfer of energy from the outputv of tube 31 to the input of tube 38, while the coupling C carries circuit units as-A sociated with the elements of tube 33 which are illustrated asianv oscillator. The receiving system need not be described in further detail as this may take various forms according to the wishes of the radio engineer or manufacturer of the receiving set.

However, to complete the circuit connections between the coupling units and the other parts of the system, I have provided switch contact members preferably carried by the same frame that supports the coupling units which have been described. These contacts are also in the form of units as shown by Figure 15, one unitfor each coupling unit. 'Ihe contact unit comprises an.

insulator 40 having holes 4| therein for attaching the insulator to the base or framework in any satisfactory manner as by rivets or screws 42. The insulator 40 preferably has a plurality of spaced openings 43 to increase the surface resistance between the several metallic contact members 44 mounted thereon. The members 44 are shown perspectively in an enlarged view in Figure 16. Preferably the metal is of good conducting material such as spring copper or bronze and has upstanding lugs 45 with inwardly projecting fingers 46,0n opposite sides of a pair of switch contacts 41, the free ends of which preferably have formations suitable for making good wiping'contact with' the switch blades 23 of the circuit units.

As will be seen from Figure 16, the metal is -cut out at 48 -between the projections 45 -and the switch blades 41 so as to give the switch blades 41 as much flexibility as possible. `As will be seen from Figures 15 and 2, the ilngers 46 are bent over the narrow portions 49 of the insulator 40. Also, the ,insulator is provided with holes 50 through which the projecting ends 5l of the contact members extend, the ends 5I being provided with holes or notches I2 for making conductor connection thereto. Y

From what has been said, it will be seen that the contact members, including the contact blades 41, are securely locked in position onthe insulator 40. The insulator 40 and its contact blades are mounted as shown in Figures 1 and 2 and other figures, so that as the coupling unitsv are rotated by means of the shaft Il, the switch blades 23 of the circuit units, which blades extend through the casing members 4, are brought into successive engagementl with the switch blades 741. These switch contacts are lettered in Figure l5 as a, b, c and d to correspond with the similar characters in Figure 2l. In other words, the wires of the system are brought to the contacts a, b, c and d of the insulators 40 which are carried on the framework of the unitary structure as has been described.

It may be noted that the .driving plate l at the operating end of the unit is provided with small openings or indentations 53 which are adapted to cooperate with a stop or positioning member in the form of a ball 54 carried in a spring 55 supported on the end of the frame, so that as the knob 2| is turned, the rotating coupling units will be positively positioned when the switch blades of the circuit unit, for a given wave band, are brought into contact with the stationary switch contacts carried by the various insulators 40. In the construction shown in Figure 18, the ball 54 is positioned in a hole in the spring 55, being permanently held therein by the bent-over part of the spring 56, so 'that when the coupling units are removed from the frame, the ball 54 is still heldin position by the spring 55. Thus it will not fall out of position'and become lost or cause trouble in re-assembling.

It may be mentioned that the casing 4 or shield screen may be brought to the potential of one end of one of the coils in a very easy and expeditious manner by *providing one of the switch blades 23 with a lug 51 having an end 58 inturned and projecting intoone of the mounting holes 21, so that when this hole is tapped for the purpose of mounting the frame of the circuit unit to the shield 4, thevtap will cut a thread'in the portion 53 so that the mounting screw 26 will make contact with the shield screen 4 and a switch blade as has been described. Thus each shield screen the various coupling units may be at different potentials.

From the description, it will be observed that I have provided a plurality of radio frequency impedances arranged so as'to tune a plurality of wave bandsfall mounted in a single unitary structure composed of electrically shielded coupling units carrying within circuit units adapted to be connected into a system so that wave bands of various lengths may be brought into tuning arrangement.

It will be apparent that various changes may be made in the details entering into the arrangement of the mechanism without departing from the spirit of the invention or the scope of the appended claims.

Fbr example, the shaft l0 may be attached directly to the end cap 5 and, if necessary, insulated therefrom; or the shaft I0 may be of insulating material.

What I claim-is:

l. A combined multi-band velectrical structure and switching mechanism for electrical circuits comprising a'supporting frame and a plurality of coupling units carried by the frame, each unit including a shielding casing having a plurality of vindividual circuit units arranged around the inner periphery of i-tsv casing, said circuit units including impedances and contacts connected thereto, said contacts extending throughthe casing, contacts carried by the frame to be engaged by said contacts projecting from the casing units, means for mechanically operating one coupling unit by means of another, and means for moyinlg the entire coupling structure with respect to the fra-me to cause diierentsets of said movable contacts to engage said contacts carried by the frame.

2. A combined multi-band electrical structure and switching mechanism as setvforth in claim 1, further characterized in that the mechanical means for operating one coupling unit from the other comprises insulators positioned in adjacent casing parts of diiferent coupling units.

3. A combined multi-band electrical structure and switching mechanism as set forth in claim 1, further characterized in that the shielding casings are of metal and have removable end caps, said caps having depressions therein carrying insulators which act as driving means from one casing unit ot the other, as well as to assist in insulating the units one from the other.

4. A combined multi-band electrical structure and switching mechanism as set forth in claim 1, further characterized in that said contacts extending from each of the casings are in the form of switch blades, while the contacts on the frame are in the form of iiexible blades to cooperate with said switch blades to secure good electrical contact.

5. A combined multi-band electrical structure and switching mechanism as set forth in claim 1, further characterized in that the coupling unit casings are drawn up from metal having one end integral with the side walls and closed by a metal cap having depressions, the bottom of one casing having depressions therein in alignment with the depressions in the casing cap of the next adjacent unit, and insulators fitting in said depressions to at least provide driving means from one casing unit to the next adjacent one.

6. A combined multi-band electrical structure and switching mechanism as set forth in claim 1, further characterized in that the coupling unit casings are of metal and circular in shape with the bottom of one casing being closely adjacent the top of another, said top having a cover for closing the casing, the mechanical means for operating one unit from the other including insulator-fitting-cooperating parts in adjacent unit casings.

7. A combined multi-band electrical structureand switching mechanism as set forth in claim 1, further characterized in that the coupling units are, insulated one from the other, and from the frame.

8. A combined multi-band electrical structure and switching mechanism as set forth in claim 1, further characterized in that end plates are drivingly but detachably positioned at opposite ends of said coupling units, said end plates having stub shafts for rotatably supporting the entire electrical structure on the frame.

9. A combined multi-band electrical structure and switching mechanism as set forth in claim 1, further characterized in that end plates are drivingly but detachably positioned at opposite ends of said couplingunits, said end plates having stub shafts for.rotatably supporting the entire electrical structure on the frame, said stub shafts being supported in detachable bearing plates carried by the frame.

10. A combined multi-band electrical structure and switching mechanism as set forth in claim 1, further characterized in that end plates are drivingly but detachably positioned at opposite ends of said coupling units, said end plates having stub shafts for rotatably supporting the entire electrical structure on the frame, said stub shafts being supported in bearing plates slidably mounted on portions of said frame, whereby the entire electrical structure may be quickly removed from the frame for the purposes described.

11. A combined multi-band electrical structure and switching mechanism as set forth in claim 1, further characterizedin that end plates 75 are drivingly but detachably positioned at opposite ends of said coupling units, said end plates having stub shafts for rotatably supporting the entire electrical structure on the frame, said stub shafts being supported in bearing plates slidably mounted on portions of said frame, said frame having notches and guiding means at opposite ends for said plates, said plates having formations to cooperate with said guiding means, and means for locking said plates in operative position on the frame. 12. A combined multi-band electrical structure and switching mechanism as set forth in claim l, further characterized in that end plates are drivingly but detachably positioned at opposite ends of said coupling units, said end plates having stub shafts for rotatably supporting the' entire electrical structure on the frame, said end plates being insulated from the coupling unit casings and the driving connections from the plates being through insulators similar to those used between the coupling units.

13. A combined multi-band electrical structure including a plurality of coupling units, each unit comprising a casing having separate impedance devices for responding to electrical impulses of a plurality of frequency bands and arranged around the inner periphery of its casing` contacts for said impedance device extending through said casing, other contacts separate from the casing to be engaged by the first-mentioned contacts, said units being so arranged and driven one through the other that the impedance devices` for a given frequency band of the different units may be simultaneously brought into cir- -cuit through said contacts.

14. A combined multi-bandA electrical structure and switching mechanism as set forth in claim 13, further characterized in that in a plurality of the individual coupling units, the values of the impedances in the individual circuit units in one coupling unit are so adjusted in relation to lthe values of the impedances in the corresponding circuit units of the other coupling units that the coupling units will at ail times respond to electrical impulses having the same difference in frequency when the values of external apparatus connected to said units remain identical.

15. A combinedelectrical structure as set forth in claim 13 further characterized in that the impedance devices for each coupling unit are shielded from the impedance devices of the other units and are also arranged to reduce parasitic effects of the said devices on the device connected into circuit.

16. A coupling unit for a structure herein described. comprising a shielding casing carrying projecting switch contacts, a. plurality of im- Pednces for responding to electrical impulses of a plurality offrequencies positioned within the casing and connected to said switch contacts, said casing being constructed for and provided with means for making a driving connection with the next adjacent unit when assembled in said structure and means for moving said unit to switch said impedances into said circuit.

17. A combined multi-band electrical structure asset forth in claim 1, further characterized in that the contacts carried by the frame comprise metallic members having a central portion embracing three sides of an insulating bar and having blades extending upwardly in close proximity to each other away from said bar, said metallic members having fingers disposed on opposite vsides of said bladesand bent over the fourth side of said bar, and means on said metallic members for making wire connections thereto.

18. In a combined multi-band electrical structure as set forth in claim 1, further characterized in that connections are made t'o said circuit units through switch contact units each comprising an insulator fastened to the frame and having a plurality of spaced openings therein, metallic members having portions wrapped around that part of the insulator forming the sides of said openings, contact blades extending from said metallic members, and means for making wire connections to said metallic members.

19. In a combined multi-band electrical structure as set forth in claim 1, further characterized in that connections are made to said circuit units through switch contact units each comprising an insulator fastened to the frame and having a plurality of spaced openings therein, metallic members having portions wrapped around that part of the insulator forming the sides of said openings, contact blades extending from said metallic members, said insulator having holes therein along one edge and terminal strips extending from said metallic members through said holes to a` point where .wires may be connected thereto.

20. A circuit connection unit for an electrical structure of the class described comprising an insulator having means on one edge for mounting the insulator to a support, said insulator having spaced openings forming bars therebetween, metallic members having spaced parts wrapped around said bars, contact blades positioned between-said spaced metallic parts and extending from said metallic members, said insulatorhaving holes along the edge opposite the mst-mentioned edge, and terminal portions of said metallic members .extending through said holes and to a point where wire connections may be made thereto.

21. A combined multi-band electrical structure and switching mechanism as set forth in claim 1, further characterized in that end plates are drivingly but detachably positioned' at opposite ends of said coupling units, said end plates having stub shafts for rotatably supporting the said bent-over end, and-means on entire electrical structure on the frame, and further characterized by having a spring supported by the frame and carrying a stop-positioning device, and means on at least one of said end plates for cooperating with said stoppositioning device.

,22. A combined multi-band electrical structure and switching mechanism as set forth in claim 1,y further characterized in that the end members of said structure have stub shafts for rotatably supporting the entire electrical structure on the frame, and further characterized by having a spring supported on the frame and carrying a stop-positioning device, and means on at least one of the end members for cooperating with said stopnpositioning device.

23. A combined multi-band electrical structure and switching mechanism as set forth in claim 1, further characterized in that end plates are drivingly but detachably positioned at opposite ends of said coupling units, said end plates having stub shafts for rotatably supporting the entire electrical structureren the frame, and further characterized by having a spring carried by the frame and having an opening therein and one end bent over said opening, a ball positioned in said opening and retained therein by the end platel adjacent said spring for cooperating with said ball to positively position said structure as it is rotated.` A

24. A combined multi-band electrical structure including a frame and a plurality of coupling units rotatably carried by the frame, each unit comprising a shielding casing carrying a plurality cf circuit units therein, said circuit units including impedances for responding to electrical impulses of different frequencies, said coupling units being held together by parts of said frame, the driving connections to and through the coupling units being made through insulators.

25. A combined multi-band` electrical structure and switching mechanism as set forth in claim 1,

further characterized in that shaft supportingmeans are attached to the opposite end coupling units.

GALE HARRISON. 

